1. Field of the Invention
The present invention relates to an image pickup apparatus that shoots a subject viewed through a viewfinder, a control method therefor, and a computer-readable storage medium storing a program for causing a computer to implement the method.
2. Description of the Related Art
In recent years, a number of cameras which have an information display unit, typified by a TFT liquid crystal display, mounted on a back side of the camera so as to display states of the camera. Among such cameras, there are those equipped with an eye proximity sensor for automatically turning off display on the information display unit because a display surface of the information display unit is dazzling when a user looks through a viewfinder. This eye proximity sensor merely detects whether or not an object has approached, and in general, an infrared sensor is used as the eye proximity sensor.
On the other hand, cameras in which a touch panel for detecting user's operations is mounted on the display surface of the information display unit have come on the market. In general, the viewfinder, the eye proximity sensor, and the information display unit are provided on the back side of the camera. Thus, in cameras of which eye proximity sensor and touch panel are operated in combination, there may be a case where erroneous operation occurs due to the tip of a user's nose touching the touch panel when the user looks through the viewfinder.
To address this, it is described in Japanese Laid-Open Patent Publication (Kokai) No. 2001-059984 that in a camera, the touch panel is prohibited from being operated according to detection outputs from the eye proximity sensor, thus preventing erroneous operation. Also, it is described in Japanese Laid-Open Patent Publication (Kokai) No. 2004-165934 that in an image pickup apparatus, an operation on the touch panel is switched to an operation different from that in normal cases so as to be isolated from contents displayed on the information display unit so that erroneous operation can be prevented.
However, the conventional image pickup apparatuses described above present problems explained hereafter. The techniques described in Japanese Laid-Open Patent Publication (Kokai) No. 2001-059984 and Japanese Laid-Open Patent Publication (Kokai) No. 2004-165934 relate to the prevention of erroneous operation in the touch panel when the user looks through the viewfinder, but do not contribute at all to preventing malfunction of the camera resulting from false detection by the eye proximity sensor.
Specifically, according to Japanese Laid-Open Patent Publication (Kokai) No. 2001-059984, when the user operates the touch panel with a fingertip while not looking through the viewfinder, if the eye proximity sensor determines the user's fingertip as the face, the information display unit turns off despite the user's intent.
Also, according to Japanese Laid-Open Patent Publication (Kokai) No. 2004-165934, when the user operates the touch panel with a fingertip while not looking through the viewfinder, if the eye proximity sensor determines the user's fingertip as the face, contents displayed on the information display unit change despite the user's intent. This makes it impossible to perform desired operations.
A description will now be given of this problem with reference to FIG. 7. FIG. 7 is a view showing an appearance of a back side of a conventional digital single-lens reflex camera. When the user tries to change shooting conditions by touching an area where an aperture value “F8.0” is displayed on a TFT liquid crystal display 732 having a touch panel in the digital single-lens reflex camera 731, a problem explained hereafter may arise. The area where the aperture value “F8.0” is displayed is close to an eye proximity sensor 734, and hence the eye proximity sensor 734 may falsely detect the user's fingertip as a user's eye looking through a viewfinder 738. Due to this false detection, the camera 731 determines that the user is going to perform shooting, and turns off display on the TFT liquid crystal display 732. Namely, when the user is trying to touch the area where the aperture value “F8.0” is displayed, an erroneous operation occurs in which display is turned off, making it impossible to change shooting conditions.